// APS101, Winter 2009: Lecture 19 (Feb. 26)
//
// Review: last time we wrote the Grades class, with two methods:
//
// Grades.passFail(-1)
// Grades.passFail(200)
// Grades.passFail(50)
// Grades.passFail(49)
//
// Grades.letterGrade(-1)
// Grades.letterGrade(200)
// Grades.letterGrade(70)
//
// we also learned about StringTokenizer...
// import java.util.*;
// StringTokenizer st = new StringTokenizer("This is a test.")
// st.hasMoreTokens()
// st.countTokens()
// st.nextToken()
// st.nextToken()
// st.nextToken()
// st.nextToken()
// st.hasMoreTokens()
//
// by default, spaces (and a few other things) are used as delimiters.
// but what if we want to specify our own delimiters?
//
// StringTokenizer st = new StringTokenizer("Barack Obama; Hilary Clinton; John McCain", ";")
// st.countTokens()
// st.nextToken()
// st.nextToken()  // what's the problem here?
// st.nextToken()  // (there is an unnecessary space at the beginning!)
//
// to try to fix this, we can specify more than one delimiter...
// StringTokenizer st = new StringTokenizer("Barack Obama; Hilary Clinton; John McCain", "; ")
// st.countTokens()
// st.nextToken()
// st.nextToken()
// st.nextToken()
//
// what's the problem now? it breaks "Barack Obama" into two tokens, "Barack" and "Obama"

// you can also specify other delimiters. Ex:
// StringTokenizer st = new StringTokenizer("Barack, Obama; Hilary, Clinton; John, McCain", ";,")
// (hint for A2!)
//
// now, let's write a game where you have to guess a number that is generated randomly,
// and the program will tell you whether your guess is too high or too low (or correct).
//
// we need to use the Random class...
// import java.util.Random;
// Random r = new Random()
// r.nextInt(10)
//
// (take a look at HighLow.java)
//
// let's start playing...
// HighLow h = new HighLow(10)
// h.makeGuess(5)
// h.makeGuess(3)
// h.makeGuess(4)
// HighLow h = new HighLow(10)
// h.makeGuess(5)
//
// what if we want to make this game more user-friendly?
// we can write a GUI for it - a Graphical User Interface
//
// import javax.swing.JOptionPane;
//
// String inp = JOptionPane.showInputDialog("Enter a number:")
// int inp = JOptionPane.showInputDialog("Enter a number:") // doesn't work!
// JOptionPane.showMessageDialog(null, "Test! Can you see this message?")
//
// (take a look at HighLowGUI.java)
//
// HighLowGUI h = new HighLowGUI(10);
// note: no need to pass a number to makeGuess anymore
// h.makeGuess()
// h.makeGuess()
// h.makeGuess()
//
// h = new HighLowGUI(100000);
// h.makeGuess()
// h.makeGuess()   // how many more times?!
//
// let's use a "while" loop 
// (take a look at HighLowGUI2.java) <- we'll go over this next time
//
// Also, you can read about the "for" loop
// (it will be useful to you for the Spy class in A2)
//
// Here is the syntax:

/*
  
  for (initialization; condition; increment or update){
    body;
  }
  
 Note:
    * The initialization expression initializes the loop; 
      it's executed once, as the loop begins.

    * When the termination expression evaluates to false, 
      the loop terminates.

    * The increment expression is invoked after each iteration 
      through the loop; it is perfectly acceptable for 
      this expression to increment or decrement a value. 
*/

// example, increasing
for (int i = 0; i < 10; i++){
  System.out.println(i);
}

// example, decreasing
for (int j = 8; j > 2; j--){
  System.out.println(j);
}

// the following causes an infinite loop... why?
for (int j = 8; j > 2; j++){
  System.out.println(j);
}